Water Efficiency Calculator

Water Efficiency Calculator

A Drought Response Tool That Really Works

RDN, in concert with technical experts in the field of water resource management, has designed a Water Efficiency Calculator (watch the webinar here) as a powerful tool for water agencies’ use. Our calculator enables water agencies to recognize which customers use water efficiently, under legislative guidelines (or variable inputs set by an agency), and identify customers who use water inefficiently.

This tool provides water agencies with a targeted public outreach option. As a result, the data and analysis we are able to provide can make necessary efforts to meet drought restrictions more effective with water agencies’ time and money, with the ability to target those customers who waste water and/or do not meet the drought goal through a focused public outreach campaign. We help to provide agencies a direct path to those customers who need to reduce water usage in order to meet agency requirements.

RDN recently demonstrated this tool during an educational workshop for board members of a Southern California water agency. Specifically, the functionality of the calculator was demonstrated as a value-add tool during water supply emergencies (drought or other). The examples below were taken from actual customer data and show (1) the customer’s water budget (based on CA guidelines, 80% evapotranspiration, and 55gpd indoor target use), (2) the actual customer’s use, and (3) an adjusted water budget given the CA request for a 20% drought usage reduction.

Components of the graph below: The solid black line represents actual use (monthly billing). The blue line with triangles represents a water budget using number of residents (U.S. Census defaults or actual number of residents) and irrigated landscape square footage (obtained from our teaming partner, Eagle Aerial Solutions). The dotted black line is the individualized water budget adjusted for the 20% reduction request by the Governor of California.  The blue and green portions of each month’s usage bar are the indoor and outdoor water allocations, respectively.  In the examples below, CA legislative guidelines are used for indoor and outdoor allocations.

Customer A, for the selected time period, uses water over and above CA’s guidelines.  This person would be an ideal target for agency drought outreach.

inefficient customer

Customer B (coincidentally, with a larger comparative lot size), for the selected time period, uses water very efficiently.  The individualized usage graph even shows the spike in actual water use resulting from an indoor leak.  This person would not be an ideal target for agency drought outreach since he/she already uses water very efficiently.

efficient customer

In the short term, the Water Efficiency Calculator helps agencies identify who are efficient and inefficient water users, accurately target the biggest water wasters for the highest conservation payoff, use staff and monetary resources effectively, and avoid the public relations pitfall of asking already efficient water users to conserve more.  In the long term, the Water Efficiency Calculator helps to reduce water waste and move agencies towards longer-term conservation goals (such as CA’s 20 x 2020 legislation).  Data used by the calculator can be used to populate a financial model to test the impact of water budget rates as well.

For further detail on the application and functionality of the Water Efficiency Calculator, please watch Eagle Aerial Solution and RDN’s webinar.